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From: coolidge@speaker.sgi.com (Don Coolidge)
Newsgroups: comp.sys.hp
Subject: Re: All you HP experts, please HELP me................
Summary: It's More Complicated Than That
Keywords: Ethernet, ARP, 802.3, Probe
Message-ID: <1990Dec20.220149.26356@odin.corp.sgi.com>
Date: 20 Dec 90 22:01:49 GMT
References: <52129@eerie.acsu.Buffalo.EDU>
Sender: news@odin.corp.sgi.com (Net News)
Reply-To: coolidge@speaker.UUCP (Don Coolidge)
Organization: Silicon Graphics Inc., Mtn. View, CA
Lines: 50

In article <52129@eerie.acsu.Buffalo.EDU> v087mxgb@ubvmsa.cc.buffalo.edu writes:
>
>My company uses an HP3000/960 for their MIS/data processing
>dept. I in Engineering run a software package on a SUN
>Sparcstation (no other choice, thats all it runs on)......
>
>Anyway, we have a database system by ASK that requires
>"block mode" terminal emulation. 
>
>How can I emulate this on my Sparc so I can have access to
>our HP and be a team player here ????
>
>This is urgent, please offer any suggestion you can.

Access to the HP3000 will take more than just block mode terminal emulation,
if that access is to be over a network.

HP3000/960 runs the MPE/XL operating system. Native MPE/XL communicates
over a LAN using IEEE802.3 packet encapsulation exclusively, not Ethernet.
It resolves IP addresses to MAC addresses using the HP-proprietary Probe
protocol. Neither Ethernet nor ARP are supported.

Your Sparcstation uses _only_ Ethernet and ARP. Without a common address 
resolution protocol or encapsulation method, the two boxes can't understand
each other. Hence, you have a certain interoperability problem...

There are a few solutions. 

1) You could put a (cisco/Wellfleet/HP) gateway in between the two boxes; those
   particular gateways speak both ARP and Probe, and both Ethernet and 802.3. 
   Note: the HP gateway could be any HP unix box; I also saw HP-labelled
   routers at the HP booth at InterOp last October.

2) You could contact your HP rep to find out if ARP and Ethernet are supported
   on MPE/XL yet - they've been supported on MPE/V for some time now, but I
   don't know what the current state of affairs is on XL. In any event, it
   probably wouldn't be part of the native MPE/XL release, but would be an 
   add-on.

3) Of course, if your access to the 3000/960 is to be by something other than
   a network (modem w/Sparcstation as dumb terminal, or some such), none of
   these problems apply.

This interoperability situation (HP3000<->Unix box) is one that comes up often
in this newsgroup. It's surprising how many people get bitten by it. 

Fortunately, the solutions are easy.

- Don Coolidge
coolidge@speaker.wpd.sgi.com